package org.ops.ui.editor.swing.ash;

/*
 * SyntaxUtilities.java - Utility functions used by syntax colorizing
 * Copyright (C) 1999 Slava Pestov
 *
 * You may use and modify this package for any purpose. Redistribution is
 * permitted, in both source and binary form, provided that this notice
 * remains intact in all source distributions of this package.
 */

import javax.swing.text.*;
import java.awt.*;

/**
 * Class with several utility functions used by jEdit's syntax colorizing
 * subsystem.
 *
 * @author Slava Pestov
 * @version $Id: SyntaxUtilities.java,v 1.2 2007-02-28 00:36:31 meboyce Exp $
 */
public class SyntaxUtilities {
  /**
   * Checks if a subregion of a <code>Segment</code> is equal to a
   * string.
   * @param ignoreCase True if case should be ignored, false otherwise
   * @param text The segment
   * @param offset The offset into the segment
   * @param match The string to match
   */
  public static boolean regionMatches(boolean ignoreCase, Segment text,
      int offset, String match) {
    int length = offset + match.length();
    char[] textArray = text.array;
    if(length > text.offset + text.count)
      return false;
    for(int i = offset, j = 0; i < length; i++, j++) {
      char c1 = textArray[i];
      char c2 = match.charAt(j);
      if(ignoreCase) {
        c1 = Character.toUpperCase(c1);
        c2 = Character.toUpperCase(c2);
      }
      if(c1 != c2)
        return false;
    }
    return true;
  }

  /**
   * Checks if a subregion of a <code>Segment</code> is equal to a
   * character array.
   * @param ignoreCase True if case should be ignored, false otherwise
   * @param text The segment
   * @param offset The offset into the segment
   * @param match The character array to match
   */
  public static boolean regionMatches(boolean ignoreCase, Segment text,
      int offset, char[] match) {
    int length = offset + match.length;
    char[] textArray = text.array;
    if(length > text.offset + text.count)
      return false;
    for(int i = offset, j = 0; i < length; i++, j++) {
      char c1 = textArray[i];
      char c2 = match[j];
      if(ignoreCase) {
        c1 = Character.toUpperCase(c1);
        c2 = Character.toUpperCase(c2);
      }
      if(c1 != c2)
        return false;
    }
    return true;
  }

  /**
   * Returns the default style table. This can be passed to the
   * <code>setStyles()</code> method of <code>SyntaxDocument</code>
   * to use the default syntax styles.
   */
  public static SyntaxStyle[] getDefaultSyntaxStyles() {
    SyntaxStyle[] styles = new SyntaxStyle[Token.ID_COUNT];

    styles[Token.PREPROC] =  new SyntaxStyle(new Color(0x9900CC),false,false);
    styles[Token.COMMENT1] = new SyntaxStyle(new Color(0x0000CC),true,false);
    styles[Token.COMMENT2] = new SyntaxStyle(new Color(0x9900CC),true,false);
    styles[Token.KEYWORD1] = new SyntaxStyle(new Color(0xCC9900),false,true);
    styles[Token.KEYWORD2] = new SyntaxStyle(new Color(0x00AA00),false,false);
    styles[Token.KEYWORD3] = new SyntaxStyle(new Color(0x009999),false,false);
    styles[Token.LITERAL1] = new SyntaxStyle(new Color(0xCC0000), false,false);
    styles[Token.LITERAL2] = new SyntaxStyle(new Color(0x009999),false,true);
    styles[Token.LITERAL3] = new SyntaxStyle(new Color(0xCC0000), false,false);
    styles[Token.LABEL] =    new SyntaxStyle(new Color(0x669999),false,true);
    styles[Token.OPERATOR] = new SyntaxStyle(new Color(0x050505),false,true);
    styles[Token.INVALID] =  new SyntaxStyle(new Color(0xFF0000),false,true);
    styles[Token.ERROR] =    new SyntaxStyle(new Color(0xCC0000),true,true);
    styles[Token.WARNING] =  new SyntaxStyle(new Color(0xCC5500),true,false);

    return styles;
  }

  /**
   * Paints the specified line onto the graphics context. Note that this
   * method munges the offset and count values of the segment.
   * @param line The line segment
   * @param tokens The token list for the line
   * @param styles The syntax style list
   * @param expander The tab expander used to determine tab stops. May
   * be null
   * @param gfx The graphics context
   * @param x The x co-ordinate
   * @param y The y co-ordinate
   * @return The x co-ordinate, plus the width of the painted string
   */
  public static int paintSyntaxLine(Segment line, Token tokens,
      SyntaxStyle[] styles, TabExpander expander, Graphics gfx,
      int x, int y) {
    Font defaultFont = gfx.getFont();
    Color defaultColor = gfx.getColor();

    int offset = 0;
    for(;;) {
      byte id = tokens.id;
      if(id == Token.END)
        break;

      int length = tokens.length;
      if(id == Token.NULL) {
        if(!defaultColor.equals(gfx.getColor()))
          gfx.setColor(defaultColor);
        if(!defaultFont.equals(gfx.getFont()))
          gfx.setFont(defaultFont);
      }
      else
        styles[id].setGraphicsFlags(gfx,defaultFont);

      line.count = length;
      x = Utilities.drawTabbedText(line,x,y,gfx,expander,0);
      line.offset += length;
      offset += length;

      tokens = tokens.next;
    }

    return x;
  }

  // private members
  private SyntaxUtilities() {}
}
